Prothonotary Warbler

Sunday, 23 March 2014

Gulls, anyone?

Gulls aren't many people's favourite birds. To the average person, they are 'seagulls' (for some reason they are not lake gulls or river gulls, or...). Some people have more derogatory names for them.

Birders are, on average, much more appreciative of them. There are some birders who are hard-core 'larophiles', since the Latin family name for gulls is Laridae. Approximately 25 species of gulls have occurred in North America, with at least 20 species being recorded in Ontario. Only a few species are considered 'common' and so especially during gull migration, birders attempt to sort through an aggregation of sometimes thousands of gulls, hoping to find a rarity or two.

Some people may view gulls as congregations of noisy messy birds, and if you have waterfront property or a boat moored at the dock, they can be both messy and annoying. But gulls are an important element of the natural world. For example they play a major role in cleaning up the beaches, feeding on thousands of dead fish that wash ashore (remember in the 1960s through the early 1980s, for example, when the huge quantities of smelt washed ashore on Lake Erie? Then after a few days of baking in the sun and heat really lived up to their name?). Gulls also eat an enormous amount of insect pests in the agricultural fields. And they themselves may end up being dinner for some higher order predator. Gulls mostly nest on the ground, and their eggs and chicks are invaluable sources of food for snakes, hawks, foxes, raccoons, etc.

Even during the winter, there are dead fish on the ice or near open patches of water. The following image shows a second year Herring Gull cleaning up a dead fish pulled from a nearby hole in the ice.

Identifying some of these gulls can be challenging, especially since most species take at least two years to attain their full adult plumage while others may take up to 4 years. The variations in their plumage due to feather moult over those several years, the occasional hybridization with similar species, as well as some geographic variation can, on occasion, leave even the experts confuddled about an individual gull's identity.

Regardless of the challenges, I find gulls fascinating in their appearance and behaviour. I am not a larophile by any means, and I confess to being uncertain on the exact species identity and age more often than I like. But therein lies the challenge of birding.....

This is the time of year when the adults are in their beautiful (yes, that is an appropriate term to describe their appearance) breeding plumage. The whites are immaculate, and in combination with the various shades of gray feathering and distinctive bright colouring of their fleshy parts, really makes observing gulls a treat. In addition, their posturing and vocalizations can be quite entertaining.

I spent a few hours yesterday (March 22) at Lighthouse Cove, located at the mouth of the Thames River in Essex County. There was very little open water, and lots of woody debris which had washed downstream late last year and remained frozen in the ice. And there were lots of gulls!

Two species of gull are the most common in southern Ontario at the moment: Herring Gull and Ring-billed Gull. Herrring Gulls are one of the largest and most common gulls. It is more or less a resident of this area, although the numbers fluctuate widely since most will go farther north to breed. However some will remain to breed locally on small islands in larger bodies of water, such as Rondeau Bay. Adult Herring Gulls are distinctive due to their large size, pink legs and the red and black spots on the lower part of their otherwise yellowish bill, as shown in the next photo.

The male is usually a bit larger than the female. The photo above shows a mated pair, with the male at the back, vocalizing about their courtship ritual......perhaps it is part of their display as they prepare to feast on fish remains.

Many times when you see a gull feeding on dead fish, they are picking it apart and taking small bites, but that isn't always the case. By nibbling away a bit at a time, the bird may risk having the rest of the fish snatched away by another gull.

Here these same two Herring Gulls are trying to protect their dinner from the clutches of a Ring-billed Gull at the right which, although is smaller, may be brave enough (or hungry enough), to risk snatching it.

Therefore when possible, they may swallow it whole. It is surprising how large of a fish can go down the hatch, as the following two photos demonstrate! These two photos were taken 5 seconds apart, and 5 seconds later the fish had disappeared.

Ring-billed Gulls are sometimes even more common than Herring Gulls, and nest in large loose colonies. The adult Ring-billed Gulls are considered medium-sized gulls and are easily identified by their bright yellow legs and the black ring around the tip of the bill. A close-up view shows the bright orange inside of their mouth as well as the reddish orange ring around the eye. As the breeding season winds down, these bright colours will diminish, although the yellow legs will still be evident.

Adult Ring-billed Gull

The sky was heavily overcast and the light subdued at the time I was at Lighthouse Cove yesterday. I tried to capture the intensity of colours these Ring-billed Gulls would have under different light conditions but was unsuccessful. Therefore I will go into my archives and post a photo I took almost exactly three years ago, at Erieau. The intensity of colour was the greatest I have ever captured, and I caught the adult making his case known to someone quite vociferously! I wonder if the gull on the left is feeling just a little bit hen-pecked?

Anytime there is food to be had, there may be quite the feeding frenzy including boisterous vocalizations and wing-flapping as demonstrated by the Ring-billed Gulls below. Gulls come and go, and while a gull may be protecting its dinner from one potential marauder another one might sneak in undetected and take off with it, only to be pursued by those gulls left empty-handed. Depending on the length and intensity of the pursuit, the snatcher may decide it is in its best interest to give it back!

Next time you have the chance, I highly recommend that you take a closer look at the antics of these intriguing characters!